test: replace content hashes and full hashes to placeholders in css extract plugin cases

[LingyuCoder]

Summary

don't want to flush hashes in plugin tests anymore

This pull request includes multiple changes to the tests/plugin-test/css-extract/TestCases.test.js file and several other test files to improve the handling and comparison of hashes in test cases. The most important changes include the addition of functions to normalize paths and retrieve hashes, modifications to the compareDirectory function to handle hashes, and updates to expected test output files to use placeholders for hashes.

Improvements to hash handling in tests:

• tests/plugin-test/css-extract/TestCases.test.js: Added functions normalizePath, getHashes, recoveryHash, and removeHash to handle and compare hashes in test cases. Modified compareDirectory to use these functions for comparing directories with hashes. [1] [2] [3]

Updates to expected test output files:

• tests/plugin-test/css-extract/cases/chunkFilename-fullhash/expected/main.js: Replaced hardcoded full hash with placeholder __FULL_HASH__.
• tests/plugin-test/css-extract/cases/es-named-export-as-is-output-module/expected/main.css and main.mjs: Updated class names to use new placeholders. [1] [2]
• tests/plugin-test/css-extract/cases/es-named-export-as-is/expected/main.css and main.js: Updated class names to use new placeholders. [1] [2]
• tests/plugin-test/css-extract/cases/hmr-locals/expected/main.css and main.js: Updated class names and full hash placeholders. [1] [2] [3]
• tests/plugin-test/css-extract/cases/hmr/expected/main.js: Updated full hash placeholder.
• tests/plugin-test/css-extract/cases/issue-6649/expected/main.js: Replaced hardcoded content hashes and full hash with placeholders. [1] [2]
• tests/plugin-test/css-extract/cases/js-hash/expected/style.$8f598b234f360ef39d24$.1.css: Removed redundant CSS rules.

Changes to hash function and digest length:

• tests/plugin-test/css-extract/TestCases.test.js: Changed hash function from md4 to xxhash64 and updated hash digest length from 20 to 16. [1] [2]

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

[netlify]

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[codspeed-hq]

CodSpeed Performance Report

Merging #9398 will not alter performance

_{Comparing test/css-extract-hashes (f38c5cf) with main (2101c1b)}

Summary

✅ 7 untouched benchmarks